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Goodwill and Intangible Assets (Tables) | 3 Months Ended
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Mar. 31, 2016
Goodwill and Intangible Assets Disclosure [Abstract] |
Schedule of Intangible Assets [Table Text Block] | Balances of intangible assets, net, excluding goodwill as of March 31, 2016, are as follows:
| December 31, 2015 |  |  | Amortization |  | March 31, 2016 |
Millions |  |  |  |  |
Intangible Assets |  |  |  |  |
Definite-Lived Intangible Assets |  |  |  |  |
Customer Relationships | $60.8 |  | $(1.1) |  |  | $59.7 |
Developed Technology and Other (a) | 7.2 |  | (0.2) |  | 7.0 |
Total Definite-Lived Intangible Assets | 68.0 |  |  | (1.3) |  | 66.7 |
Indefinite-Lived Intangible Assets |  |  |  |  |
Trademarks and Trade Names | 16.6 |  |  | n/a |  | 16.6 |
Total Intangible Assets |  | $84.6 |  |  | $(1.3) |  |  | $83.3 |
(a) | Developed Technology and Other includes patents, non-compete agreements, and land easements.

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- Definition Tabular disclosure or assets, excluding financial assets and goodwill, lacking physical substance, by either major class or business segment. + References No definition available. + Details
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